Ok Gurus out there. Some of whom may have caught my mention of this in the Bolt Action sub-forum.
I just got a new 450b barrel for one of my Savage Model 12's. I visually inspected the bore before doing anything with it. Looks Great. I got it headspaced, torqued, mounted in a nice stock and finally got around to doing some preliminary checks prior to reloading, starting with measuring the Freebore. It came out to .072 as opposed to the SAAMI spec of .200. I suspect the gunsmith who chambered it used a non-throating reamer. For the unwashed masses, you can get them either way. Ones that cut the main chamber and the freebore and ones that cut a minimum and leave the remainder to be cut with a separate throating reamer, for those who want a non-standard freebore. I contacted him and he took ownership of the mistake, offering to buy a throating reamer and cut it to whatever length I wanted. I told him to sit tight until Monday while I consider this issue.
Those of you who have followed my work, know I like lighter (shorter) bullets traveling faster as opposed to heavy (longer) bullets lumbering along. One of the limiting factors in my original 450b barrel and now the Bartz is the lighter bullets, when seated close or into the lands, tend to lack sufficient seating depth. So, I grabbed some of the lighter ones that I still have. The C.O.P. 160, 185 and 200gr as well as the 200gr FTX and XPB bullets. With the shorter freebore, I can now seat them long without running out of case. Hmmm...
This leaves me with a conundrum however. I was perfectly happy with my AR 450b but wanted to be a contributor again and all the hubbub around here is mainly concentrated on bolt actions lately. Many of which are stoked for velocity by loading them longer which affords more case capacity for powder, not to mention greater overall strength and a few other benefits.
I'm caught wanting to speed up those lighter bullets more than I ever could with my AR platform but I also want to throw some heavier bullets with thunder. I'm only out the cost to ship my barrel back to LA where the gunsmith lives to get the barrel properly throated and the turn around time. Its at least another month until comfortable shooting weather returns up here in MN so I'm not in a hurry. There is the alternate direction of wanting to seriously kick those lighter bullets in the butt. There is a compounding factor however. This new barrel is a 1:16 twist and yes, too high an RPM can make bullets come apart in flight. Yes, it is a real issue. Had this barrel been the 1:24 like my AR barrels or even a 1:32, it would be no contest. Don't get me started on why 1:16 is even made in this caliber as 1:24 is a fast enough twist for up as high as 325gr bullets, regardless of whether you choose to shoot them super or sub sonic. That's a debate for another time and place.
I started writing this with the goal of asking your feelings on which way to go but I think that just writing it down has convinced me of what needs doing.
Nevertheless, feel free to chime in with your feelings. I'm always prone to persuasion.
Hoot